The invention relates to a device for guiding a medical instrument, comprising a guide tube having a distal end and a proximal end, and having a longitudinal opening extending substantially from the distal end to the proximal end, wherein the guide tube has a rounded bottom and two parallel longitudinal side walls so that that guide tube is about semi-circular.
A device of the type mentioned before is known from EP 0 552 980 A1.
A device of the afore-mentioned type is used in the field of orthopaedics or in casualty surgery in order to facilitate the access for medical instruments to joints where surgical operations are to be carried out.
A particular field of application of such a device is the arthroscopy.
The device known from EP 0 552 980 A1 mentioned before comprises an elongated guide tube having a closed distal end, an open proximal end and a longitudinal opening or slot extending from a point near the closed distal end to a point near the open proximal end of the guide tube. The guide tube has a D-shaped cross section which extends substantially over the entire length of the tube. The flat part of the D-shaped cross section is situated along the edge of the longitudinal opening and the D-shaped cross section comprises a predetermined dimension for receiving and guiding an instrument axially inserted in the guide tube from the open end. Further, a handle is disposed at the proximal end of the guide tube of this known device, which extends in prolongation of the longitudinal axis of the guide tube.
This known device is particularly used for the treatment of the carpal-tunnel, in order to introduce instruments like an endoscope or a cutting instrument in the surgical area by means of the guide tube and to place them therein, accordingly.
A disadvantage of the known device is that the guide tube cannot be withdrawn from the surgical area when an instrument is inserted in the guide tube. Furthermore, the arrangement of the handle of the known device in axial prolongation of the guide tube is disadvantageous, because the handle represents an obstacle to the insertion of a medical instrument, for example an arthroscope, into the guide tube from the proximal end.
It is therefore an object of the present invention to improve a device of the type mentioned at the outset such that the disadvantages mentioned before are avoided, in particular the device can be easily removed from the surgical area after a medical instrument having been introduced by means of the guide tube.
According to the present invention, this object is achieved by a device for guiding a medical instrument, comprising:
a guide tube having a distal end and a proximal end, and having a longitudinal slot extending substantially from said distal end to said proximal end, wherein said guide tube has a round bottom and two parallel longitudinal side walls, so that that guide tube is substantially half-circular in cross section; and
a handle connected to said guide tube in the region of said proximal end of said guide tube,
wherein said distal end of said guide tube is open, and wherein said handle laterally projects from said guide tube.
Since the distal end of the guide tube is open, the guide tube can be easily withdrawn from the surgical area along the instruments which have been introduced in the surgical area through the guide tube. While the instruments can remain in the surgical area, the device must not remain in the joint for maintaining the access as it is the case with conventional tube systems. Since the handle projects laterally from the guide tube, a medical instrument can be introduced in the surgical area along the guide tube from the proximal end thereof without any impediments. This has the advantage that the access of a medical instrument in a joint through soft tissues is possible without obstacles. In use of the device according to the present invention, the guide tube is advanced along an instrument previously introduced into the joint until the distal end of the guide tube can be seen through an endoscope. In the next step, the medical instrument previously introduced is withdrawn, whereafter another instrument can be advanced along the guide tube into the joint. The guide tube is subsequently withdrawn from the joint, whereas the instrument previously introduced can remain in the joint.
In a preferred embodiment, the proximal end of the guide tube is open.
In another preferred embodiment, the distal end of the guide tube is chamfered.
In another preferred embodiment, the handle projects from the guide tube substantially in a right angle.
In a still further embodiment, the handle projects from one of the side walls of the guide tube.
A preferred embodiment of the present invention will be described hereinafter with reference to the accompanying drawings, in which: